Summary: Life expectancy has increased considerably in the last few decades in the US and globally. However, this has also altered the disease pattern. A new study in the US shows that one in ten adults is now living with dementia, and another 22% are living with cognitive impairment. Since life expectancy is expected to keep rising over the next few decades, the nation and healthcare system should be better prepared to manage dementia.
In the US, average life expectancy has constantly risen since the early 20th century. Although, there has been some decline in the last few years due to Covid-19. Nonetheless, on average, people in the US can expect to live 10 years longer than in the mid-20th century.
However, the aging population also means that disease pattern is changing. Aging particularly increases the risk of brain disorders like dementia and mild cognitive impairment. The risk of dementia increases with age and due to various socio-demographic factors.
There has been no study regarding the prevalence of dementia in the US for 20 years. Thus, the new study was carried out, and its findings were published in the journal JAMA in October 2022. This new study shows that one in ten Americans live with dementia, and another 22% live with mild cognitive impairment.
This new study is important in many ways. First, it is a part of the nationally representative and long-running Health and Retirement Study. It shows the actual burden of dementia in the US. This data would help track the trends for coming years or even decades. Additionally, the study is relevant considering the impact of covid-19 on life expectancy and metabolic health in the US.
Longevity and dementia
The study analyzed the data of 3500 adults in the Harmonized Cognitive Assessment Protocol (HCAP) Project. They were part of Michigan’s nationally representative Health and Retirement Study (HRS) done between 2016-17. All participants had to complete comprehensive neuropsychological tests that were good not only for detecting dementia but also mild cognitive impairment.
The study had many interesting findings. It found that increasing longevity has much to do with the increasing rate of dementia. Thus, the study found that the prevalence of dementia was about 3% in those 65 to 69; however, it increased to 35% in those 90 and over.
Researchers say that understanding this data is vital to prepare the healthcare system in the US better. Moreover, countering the rising rates of dementia and mild cognitive decline would require specific policy changes in the nation.
Doctors say that the number of people living with dementia and cognitive impairment is bound to increase with increasing life expectancy. This increase may be significant in the coming decades, and the nation must be prepared to meet this challenge.
Additionally, it is vital to understand the economic impact of rising dementia. It will result in added healthcare costs of about $250 billion in the US and close to a trillion US dollars worldwide.
Dementia and disparities
The study also had some other significant findings, like a higher prevalence of dementia in specific population groups. Thus, the study shows that apart from age, other factors associated with higher dementia prevalence are ethnicity, socioeconomic status, and education.
Data shows that dementia is more common among socially deprived people. Thus, the risk of dementia is relatively higher in African Americans. Mild cognitive decline is more common in Hispanics. Generally, cognitive decline is greater in people who did not obtain much education.
This data suggests the need for even more extensive population-based studies to understand how various factors increase the risk of dementia and cognitive impairment.
Finally, this study also shows an urgent need to improve diagnostic tools and prepare the healthcare system for upcoming problems.
